The roadmap states that the update this month includes 2-hour obtainable merited abilities for level 99 players:

Quote Originally Posted by Mocchi
*March
Expansions to the Limbus and Einherjar battlefields, along with further job adjustments and two-hour abilities obtainable via merit points are set to be introduced this month.
I propose that the merit cap be lifted in light of this from 30 to 50 or higher.

Even if the two-hour merited abilities aren't included in this update, I still propose the cap be lifted. There are numerous amounts of merit categories now that are expensive to say the least (22-30 merits for 1 upgrade) and the 30 cap just doesn't cut it.

I'd imagine all that would be required is changing a simple variable from 30, but maybe it's more difficult.